No, you aren't imagining it: There is indeed less leg room on some airplanes than there used to be.

"Back in the old days, probably 20 years ago, the tendency was to have about 34 inches," says Mark Gerchick, a former chief counsel for the Federal Aviation Administration. "Now the standard is about 31 inches in the United States. ... Some of the low-cost airlines have tightened that up to about 28 inches, which is now approaching the limits of anatomical possibility."

This is clearly not ideal. In the introduction to his new book, Full Upright and Locked Position, Gerchick writes that for most people, "the magic of air travel has morphed into an uncomfortable, crowded and utterly soulless ordeal to be avoided whenever possible."

The book goes on to explain why it's gotten that way: why we pay so much in fees, why the person sitting next to you probably paid a considerably more — or less — than you paid for a ticket, why it often feels like there's not enough air on the plane and so on.

Now an aviation consultant, Gerchick is particularly bothered by how declining quality of service is matched with a steady increase in rates.

"What I'm concerned about," he says, "is if there's some way to maintain a degree of civility and dignity about air travel without the constant extraction of additional funds."

Interview Highlights

On the in-flight air quality inside the cabin

"It's extremely dry. Almost no humidity content. What that means is that in order to humidify the inside of a cabin, what's basically humidifying the cabin is the human beings in the cabin. So: sweat, other bodily effluents, our breathing. That's what's creating most of the humidity inside the aircraft cabin in altitude. Some of the new aircraft are actually trying to improve on that. They're actually adding back humidification systems into their airplanes and trying to bring it up to 15 or 16 percent humidity. But normally the humidity levels in airplanes, because of the coldness of the outside air, is not holding humidity. Normally those levels are very, very low, similar to Death Valley in the summertime."

On tensions that can erupt over space

"A couple of years ago a United Airlines flight to Ghana from Dulles had to turn around after there was an altercation after one person tilted their seat back all the way and the person behind slapped the head of the person who had tilted the seat back. And instead of running 5,000 miles out in the middle of the south Atlantic in the middle of the night not knowing what was going on, the pilot said, 'The heck with it,' and turned around, and was accompanied by a couple of F-16s and brought the airplane back to Dulles."

On concerns associated with regional planes

"One of the key issues is fatigue. The pilots who operate the regional carriers tend to operate lots of flights into congested airspace and busy airports. Lots of takeoffs and landings. They work very hard and long hours, and they tend to be less experienced than the major airline pilots who now have thousands and thousands of hours. They're all regulated to the same extent. They all have to meet the same minimum hours and experience, but the fact is that regional carriers don't have quite the same level of experience and expertise as the majors."

On the evolution of first class

"First class is getting to be really first class. And I speak not from a lot of personal experience, but the airlines have realized that this is where a great deal of their revenue comes from. One airline once said that 25 percent of the passengers provide 75 percent of the revenue. So if you get that premium cabin filled, you're going to do well. ... Some of the upscale foreign carriers — Emirates, Singapore, long-haul Asian carriers — have thrown tremendous amounts of money into first class. ... What's in store is that some of the Middle Eastern airlines are putting bidets in their bathrooms, and Emirates has a couple of showers on their A380. So you can have a five-minute drenching ... in their spa shower. Some of the airlines have new privacy pods which they're putting in their ultra-first-class A380, where you [have] basically 7 or 8 feet of space, your own large-screen television and private minibar, and it's an enclosed space, with a full bed. At the high end now we're talking $10,000 or $20,000 a ticket, so it's not exactly available for everybody."